Fuse-plug.



J. H. HANSON & J. W. STEELE. y

FUSE PLUG. APPLICATION riLnD APR. 12, 1913.

1,103,41 1, Patented July 14, 1914 tion, and the invention refers moreparticu- View o the core. Fig. 4 is a transverse secand -heing incontact with the lower lends of all of the fuses .8 or, in other -words,with the middle portions or bends oi specification.

through, each of said openings containing a ernten.

y JOHN H. HANSON ANB JOEL il?. STEELE, 0F CHICA/1GO, ILLINOIS.

FUSE-PLUG;

Specication of Letters Patent.

Patented July 14, 1914.

Application flied April 12, 191s. serial Nd. 760,650.

To all 'whom it may] concern:

Be it known that we, JOI-IN H. HANsoN and JoHN YV. STEELE, citizens ofthe United certain new and useful Improvements in Fuse-Plugs, of whichthe following is a The object of this invention is to produce a fuseplug of novel and improved construclarly to a plug provided with aplurality of fuses arranged to be successively brought into service,such plugs being known as multiple fuse plugs.

In the accompanying drawings, Figure 1 is a longitudinal verticalsection'through a fuse plug embodying the features of our invention..Fig 2 is a plan view with the closing ca removed. f Fig. 3 is aperspective tion through the plugin the plane of line 44 of Fig.` 1.

The referred form of our invention is shown in the drawings and will beherein described in detail, but it should be understood that theinvention is not limited to the' exact structure disclosed, Ibut may beembodied in various modified forms without departing from the scope ofthe invention as defined 'in the appended claims.

The plug comprises a sleeve 5 of insulat ing 'material and a centralinsulating core 6 tting in said sleeve. Said core is provided with aplurality of openings or chainbers 7. extending longitudinally therefuse8. In the preferred form shown in the drawings four. fuses lareprovided, but it will be understood that the plug may be adapted foralarger or smaller number of fuses if desired. The fuses may be arrangedin pairs, each pair being formed from an integral strip of fuse' wire,the middle portion of the strip being bent around the lower end of thewall between two of the fuse chambers 7. A metallic Contact button 10has its shank secured in a central recess 11 in the core, the headofsaid button fitting in a recess 12 in the lower end of the core thestrips constituting said fuses. llhe free upper end of the strips whichconstitute the l'uses 8 are bentv outwardly to over-lie the upper end ofthe core, and the `extreme ends of the fuses preferably. are bentdownwardly into recesses 13 in the outer surface of the core. Said fusesmay, if desired, be secured o in said recesses by plaster of Paris orother suitable material. The lower end of the core has a head 14 formedthereon which underlies the lower end of the sleeve 5 when the parts areassembled together. The upper 5 end of the corehas a plurality of walls15 extending upwardlyl therefrom, said walls forming partitionslseparating the upper ends of the openings 7 and the exposed ends of thefuses 8 from each other. When the 7o core is inserted intothe sleeve 5,Athe upper ends of the walls 15 preferably lie substantially flush withthe upper end of said sleeve.

A metallic shell 1G surrounds the sleeve 5, said shell being spirallyindented to forni a screw thread to engage with the core 5 and Contactpiece being soldered or otherwise secured to the shell 16, and the innerend of said piece being arranged to contact one of the fuses 8 asclearly indicated in Fig; 1. Thus only one of the fuses is in service ata time. The Contact piece 17 serves to secure g5 the shell 1G rigidly tothe sleeve 5. If desired, interlockiirg iudentations 18 may be formed insaid shell and sleeve at the side opposite to the contact piece 17 tofurther assist in locking these parts together. 9U

In order to more fully insulate the fuses:- from each other and preventshort circuiting between the fuses, we provide lugs 19 projectinginwardly from the sleeve 5, said lugs abutting against the partitionwalls l5 on g5 the core and (roinpietely closing the upper ends of thefuse chambers. The lug which lies above the contact piece 17 is providedat its inner end with an opening or notch 2S) for the purpose ofventingthe fuse chain ber beneath it, as will be latter described. Saidlug forms a rigid backing for the conI tacty piece 17 and serves as aninsulating cover therefor. l

The sleeve '5 has an enlargement or ex terior ange Q0 at its upper end.ik metalli;c cap 2l having a flange 22 at its edge fils downwardly overthe flange 20, said cap being secured in place preferably by bending thelower edge of the flange 22 into an in annuiur groove 22) in theperiphery ci the flange 20. 'lhe lmver corner ci' the limpie 20 servesas an insulating wall between the cap 21 and the shell 16. The cap 21has a central opening 24 therein, and between Said cap and the upperface of the sleeve 5, flange phere through a -pair of grooves 27 in theedge of said `flange, one of the latter grooves preferably beingpositioned directly opposite the Contact piece 17. A groove'28 in theupper a'ce of the sleeve 5 connects the groovey 26 with the opening ornotch 29 extending vertically through the lug 19 which liesl above thecontact piece 17. The purpose of the grooves 26, 27 and -28 and theopening 29 is to permit the escape of gas -from the interior of the plug-when a -fuse is melted. f

In use, when the active fuse blowsf the plug will be unscrewed fromy itssocket, the core 6 withdrawn downwardly out of the sleeve and given apartial rotation to bring a new fuse into place, and the core then again'inserted into the ksleeve to carry the new fuse into Contact with thepiece 17. W'hen all of the jfuses in the core have been destroyed, theoldcore may be thrown away and anew one rfull of Afresh fuses insertedinto the sleeve. lVhen the lplug is screwed tightly into its socket, thepressure exerted on the contact button 10 will clamp the fuse 8 tightlybetween the u 'per end of the core and the Contact `piece 1i).

In the exemplary form of our vinvention which we vhave shown in thedrawings, the

central core 6 is non-circular or polygonal in cross-section and theinterior of the sleeve is correspondingly shaped to receive the core.lVhere four fuses are used, the core may be four-sided, as indicatedmost clearly in Fig. 3, the corners of the core preferably being beveledoil' as at 9. It should be understood,l however, that our invention -isnot limited to a core which is non-circular in cross section. It isdesirable -to form the core andthe sleeve in such a way that'they willinterlock to prevent relative rotation thereof when the core and sleeveare in their normal or operative position. The non-circular shape of thecore acts to prevent such relative rotation and the same -purpose iseffected by Athe ugs 19 and the partition walls 15 which interlock whenthe core is in its operative position. Therefore, it will be seenthatwhen thelnterlocking parts 15 and 19 orftheir equivalents are used,the core need not necessarily be made non-circular, and on the otherhandwhen the core is made non-circular,`itis not necessary that the parts15. and 19'be arranged to prevent relative rotation ofthe core and thesleeve. When the core is made non-circular, as shown in the drawings, itmust be fully withdrawn from the sleeve before rotation to position thenew fuse, but it will be readily understood that it' the interlockingrelation bf the lugs 19 and walls 15 or their equivalent means, bedepended upon to prevent relative rotation, the bod of the core might bemade circular in which case it would be necessary to move the corelongitudinally or axially merely a suiicient distance to disengage theinterlocking .portions 15 and 19, when the core could be rot-ated withinthe sleeve. Thus it is not essential according to our invention that thecore be fully withdrawable from the sleeve, out on the contrary anon-withdrawable core might be used, it being necessary only that thecore have a longitudinal or axial movement in the sleeve a sufficientdistance to disengage the interlocking portions of the sleeve and thecore, so that they maybe relatively rotated vto position a new fuse.

'lWe believe ourselves to be the yfirst to produce a fuse plugcomprising an inner and an outer part normally interlocked to preventrelative rotation and movable longitudinally or axially into position topermit of such relative rotary. movement.

It willbe noted that in our plug a new fuse may be substituted after ablow-out in an extremely short time and with very little trouble. Noscrews or like fastenings secure the fuses in place. It will also beseen that no spring contacts are employed, such springs beingundesirable because 'likely -to vbecome overheated land untempered. Allof the'fuses not .in use are carefully insulated from the active fuse toprevent accidental short circuits.

We cla'im as our invention:

1. A ,fuse plug comprising an outer member of insulating material, athreaded metallic shell secured thereto and adapted to be screwed'into asocket, an inner member, a plurality of fuses carried lby one of saidmembers, and a contact piece carried by the other member and adapted tocontact with one of said fuses, said members having portions engagingeach other and prevent` ing relative rotation thereof when in theiroperative relation, and said members being relatively movable in adirection to disassociate said engaging portions.

2. A fuse plug comprising an outer member of insulating material, ametallic threaded shell secured thereto and adapted to be screwed into asocket, a contact terminal carried by said shell, an inner member. aplurality of fuses carried by said inner member and arranged to besuccessively brought into operative relation to said terminal byrelative rotation ot' said members, Said members being ,shapedv toengage each other to prevent relative rotation when in their normaldinally movable with respect to each other messi;

into position to separate the engaging portions of' said members. l

3. In a fuse plug,y a body comprising a Sleeve-likeportion closed at oneend, said body 'having a non-circular opening therein,

a central insulating core wholly inclosed eX- cept at one end by saidbody, said core having a portionfitting in said opening to preventrotation of the core when in its operative position, and' a plurality offuses carried by said core, the core being longitudinally movable towithdraw said portion from said opening, whereby the core is f'ree to berotated to carry a new fuse into operative posit-ion.

4. A fuse plug comprising an outer bod7 portion of insulating material.having sccured thereto a threaded metallic shell adapted to be screwedinto a socket. said shellhaving a contact portion. a central insulatingcore in said bodyr portion. said core and body portion having engagingparts to prevent relative rotation when in their operative relation, anda plurality ot' fuses carried by said core, said co're being arranged tohave a movement longitudinall)7 ot its axis and also a rotation aboutits axis Ato succes zsively position said fuses in operative'relation tosaid contact portion.

5. ln a fuse plug, a body *comprising a sleeve-like portioii closed atone end, said body having a non-circular central opening. a Withdrawablecore wholly inclosed except at one end b v said body, said core having anon-circular portion, said opening and said core-portion being shaped topermit insertion of' said portion in said opening in any one of severalpositions. said core having a plurality ot' loiigitudinal openingstherein, a fuse in each ot' said openings, and a conf ductor carried bysaid bod)Y portion with which conductor one of said fuses is arranged tocontact.

6. A fuse plug comprising an insulating sleeve, a metallic yshellsurrounding said sleeve, an insulating core fitting into said sleeve andwithdrawable therefrom, an enlarged head on the lower end of said core,said head extending laterally beneath the lower end of said shell andforming a finger piece by which the core may be Withdrawn, a fusecarried by said core, and a Contact piece extending through said sleeve,said contact piece contacting said metallic shell at itsouter end andbeing arranged to contact said fuse at its inner end.

7. In a fuse plug, a body comprising aI sleeve-like portion closed atone end, said body having an internal opening, an insulating coreadapted to enter said opening, said opening and said core being whollyinclosed except'at ,one end by said body. said core being shaped topermit the insertion of the core in the opening in any one of severalpositions, said core and said body portion having parts engaging eachother to prevent relative rotation when the core is in its operativeposition in said body portion, and a plurality yoiffuses carried by saidcore, said body portion having a conductor arranged to contact with oneof said fuses at a time, when said core is placed in said body portionin different positions.

8. A fuse plug comprising an insulating sleeve, a metallic shell securedthereto, a core fitting in said sleeve, said core and sleeve havingengaging portions which prevent relative rotation of' the sleeve andcore when the latter is in its normal position, a plurality ofl fusescarried by said core, a contact piece connected with said shell andarranged to contact one of said iuses, and partitionv walls on one endot' said core actingI to separate and insulate the upper end of thefuses from each other.

5). A tuse plug comprising an insulating sleeve, a metallic shellsecured to said sleeve, an insulating cere extending into said shell andfitting in an opening in said sleeve, said core and said sleeve havingengaging portions which prevent relative rotation of the core and sleevewhen in their` operative relation. a plurality of fuses carried by saidcore, a conducting portion#connected with said shell and arranged tocontact one of said fuses, partit-ion walls on one end of said corearranged to separate said fuses from each other, lsaid partition wallsand said sleeve forming recesses, and inwardly projecting lugs on saidsleeve arranged to close the upper ends of said recesses.

l0. A :t'use plug comprising an insulating sleeve. an annular threadedmetallic shell secured thereto and adapted to be screwed into a socket,an insulating core polygonal in cross section extending into said shelland fitting in a corresponding central opening in said sleeve to preventrelative rotation ot the core and sleeve when in normal relation, saidcore being withdrawable longitudinally from'said central opening topermit such relative rotation, a contact-piece connected to said shell,and a. plurality of fuses. carried by said core and arranged to singlycontact said contact-piece when the core is in different positions.

11. `A fuse plug comprising an insulating sleeve, an annular`threadedmetallic shell secured thereto and adapted to be screwed intoa socket, acentral insulating core, said sleeve and said core having interengagingparts which prevent relative rotation of the sleeve and core when intheir operative 'relation. said core being movable longitudinally toseparate said engaging parts and permit such relative rotation, a -capfixed to and closing the end of said sleeve opposite to that from whichsaid core enters, a plurality of fuses carried by saidcore and arrangedto singly contact at their upper ends with a part connected to saidshell when the core is in different positions, and a contact buttonixedin the end of the core opposite to said capand Abeing exposed on thesurface soas'to'contact with a portion of the socket, the-,lower ends ofall of said fuses being in contact with said button.

12. A fuse plug comprising a body, a core having a plurality of "fuses,portions of which are exposed on the outer surface of the core, saidcore having partition walls separating said exposed portions from eachother, and said body having inwardly extending lugs cooperating withsaid partition walls to further insulate such exposed portions.

13. A fuse plug comprising a body ortion, a core therein having aplurality o recesses, fuses in said recesses, and lugs onl the bodyportion projecting inwardl and lying in' said recesses to preventrela-tive rotation of the body and the core, the latter being axiallymovable to disengage vthe recesses' and the lugs and permit rotationofthe core.

In testimony whereof we affix our signatures in the presence of twowitnesses.

